Current biology : CB
April 12, 2021
Karen R Konkoly, Kristoffer Appel, Emma Chabani et al.
126 citations
People who are asleep and having a lucid dream—aware that they are dreaming—can perceive questions from an experimenter and answer them in real time using eye movements and facial muscle contractions. In a study of 36 individuals during REM sleep, including frequent lucid dreamers, a novice, and a patient with narcolepsy, participants performed perceptual analysis of new information, held information in working memory, computed simple answers, and gave volitional replies. Correct answers occurred on 29 occasions across 6 individuals, documented by four independent laboratories. This two-way communication channel allows real-time interrogation of dream cognition and characteristics.
Nature and Science of Sleep
January 1, 2018
Anastasia Mangiaruga, Serena Scarpelli, Chiara Bartolacci et al.
40 citations
Brain and sleep maturation change across life stages, and dream generation and recall depend on neural development. This review examines dreaming in infancy, adulthood, and old age, assessing whether dream mentation reflects underlying brain activity and cognitive processes. In children, weak evidence links cognitive skills to dream features, but infantile amnesia, confabulation, and limited language are confounding factors. In adults, evidence suggests shared neural mechanisms between waking cognition and dream features. Elderly people commonly report lower dream recall frequency, attributed to diminished interest or possibly age-related cognitive decline. The authors note a lack of longitudinal psychophysiological studies and recommend future research collecting dream reports upon awakening with neurobiological and cognitive measures.
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
February 1, 2021
Jarrod Gott, Leonore Bovy, Emma Peters et al.
33 citations
Lucid dreaming—being aware that one is dreaming while still asleep—is rare but can be trained by regularly questioning whether current experience is real or a dream. Virtual reality (VR) scenarios containing dream-like elements enhanced this training. Over four weeks, volunteers who received VR-assisted lucid dreaming training showed significantly greater increases in lucid dreaming than those who received no training. Eye-signal-verified lucid dreams during polysomnography supported these behavioral results. Potential mechanisms include synthetic dream-like experiences, incorporation of VR content into dream imagery as memory cues, and dissociative effects of VR that may amplify lucid dreaming training during wakefulness.
Consciousness and Cognition
September 1, 2020
Jarrod Gott, Michael Rak, Leonore Bovy et al.
23 citations
Lucid dreaming, where people experience waking-like self-reflection during dreams, is linked to more wake-like brain activity in the prefrontal cortex. This multi-centre study, combining four investigations, examined whether fragmented sleep increases the chance of lucid dreaming. Results showed that self-reported awakenings, polyphasic sleep schedules, and physiologically measured wake-REM sleep transitions were associated with lucid dreaming. However, neither self-assessed sleep quality nor physiologically measured numbers of awakenings showed an association. The findings suggest a nuanced relationship, where certain types of sleep fragmentation, but not all, may relate to lucid dreaming, and the authors discuss possible causal mechanisms.
Journal of Sleep Research
October 1, 2021
Serena Scarpelli, Valentina Alfonsi, Anastasia Mangiaruga et al.
During the COVID-19 lockdown, a large Italian sample reported more frequent nightmares and dreams compared to a population-based sample. Predictors of high dream recall included young age, female gender, not having children, and sleep duration. High nightmare frequency was predicted by young age, female gender, changes in napping, sleep duration, intrasleep wakefulness, sleep problem index, anxiety, and depression. Higher emotional features of dream activity occurred in workers who stopped working, people with relatives or friends infected by or who died from COVID-19, and those who changed sleep habits. These findings support the continuity hypothesis linking daily experiences to sleep mentation and the arousal-retrieval model linking poor sleep to nightmares.
Brain Sciences
June 3, 2020
Serena Scarpelli, Aurora D'Atri, Chiara Bartolacci et al.
Among older adults, those who recall dreams show higher cortical arousal during NREM sleep than those who do not. In a study of 20 elders, dream recallers had lower delta power over parietal areas and higher activation index (delta/beta power) in fronto-temporal and parieto-occipital regions compared to non-recallers. No differences appeared in the last five minutes before awakening. Visual vividness and dream length correlated positively with arousal level. The findings support the activation hypothesis, which links dream recall to brain arousal, and highlight the temporo-parietal-occipital zone as crucial for storing dream content.
Sleep Medicine Reviews
April 1, 2019
Valentina Alfonsi, Aurora D'Atri, Serena Scarpelli et al.
Sleep talking is a common, non-pathological behavior involving unaware vocalizations during sleep. Despite increased knowledge about sleep cognition, research on sleep talking remains outdated. Verbal utterances often reflect ongoing dream content, offering a direct window into dreamlike mental experiences. The phenomenon is discussed within a cognitive framework, considering atypical activation of psycholinguistic circuits during sleep and the role of verbal 'replay' in memory consolidation. Analyzing sleep talking episodes could help address fundamental questions about dreaming and information processing during sleep, though further systematic polysomnographic and neuroimaging studies are needed.
Frontiers in Neurology
January 1, 2019
Serena Scarpelli, Aurora D'Atri, Chiara Bartolacci et al.
Frontal theta oscillations during the last five minutes of REM sleep predict whether older adults will recall a dream upon waking, replicating a pattern previously established in young adults. In a study of 21 healthy older volunteers (mean age 69.2) and 20 young adults (mean age 23.4), dream recall occurred when REM sleep showed rhythmic frontal theta activity. No interaction between age and recall status was found, indicating the same brain activity supports dream recall in both age groups. Theta oscillations were more abundant in young participants, and the authors distinguish this rhythmic theta from non-rhythmic theta linked to sleepiness or clinical cortical slowing.
Brain Topography
September 1, 2017
Serena Scarpelli, Aurora D'Atri, Anastasia Mangiaruga et al.
Dream recall upon awakening from NREM sleep is predicted by reduced delta activity in left frontal and temporo-parietal areas during the final segment of sleep. This finding suggests that increased cortical activation is a prerequisite for remembering dreams from NREM sleep, challenging the traditional view that dreaming is unique to REM sleep. The study used a multiple nap protocol and within-subjects design to collect dream reports after stage 2 NREM sleep awakenings. The results indicate that the brain mechanisms underlying dream recall during NREM sleep may share features with those involved in encoding episodic memories during wakefulness, though they also depend on the specific electrophysiological state of sleep.